NOW ON BOARD: Nets center Brook Lopez (right), who joked with Knicks counterpart Tyson Chandler on Saturday, knows he must rebound better this season. “I was being lazy, first and foremost,” Lopez said regarding his board efforts a year ago.Paul J. Bereswill

In establishing himself as a legitimate force, Nets center Brook Lopez had 23 double-figure rebound games and 18 double-doubles as a rookie. In his second season, those numbers increased to 34 and 33 as he also averaged 8.6 rebounds. Then came last season.

Lopez suffered from a horrid case of reboundophobia. He had nine double-doubles, his first not coming until his 19th game of the season. He heard it from coach Avery Johnson and Nets fans. The sun rose in the East, set in the West and Lopez was panned for rebounds you could count on one hand. It wasn’t even the lack of rebounds as it was a lack of trying.

“The rebound attempts were low,” said Johnson, who believes Lopez can be a 20-point, 10-rebound guy with work and determination. “So this year, we’re watching him on film. If he gets the rebound, great. But, ‘Did you attempt to go for a rebound?’ ”

In the first preseason game, Lopez did just that. He made a “conscious effort” Saturday against the Knicks and snared 11 rebounds to go with 15 points and five blocks. If he put up those numbers last year, they would have renamed the arena in his honor. The 7-foot Lopez averaged 6.0 rebounds. Figure he should at least get his hat size. True, he was away from the basket displaying a solid touch, which led to a career-best 20.4 scoring average. And the theory career-year guy Kris Humphries was taking all available boards didn’t wash.

“It was a number of things — I was being lazy, first and foremost,” Lopez said. “Hump was doing such a good job a lot of the time, that I’d see him doing his thing and kind of leak out offensively. I didn’t really crash the offensive boards. There’s really no excuse for that because I didn’t leak out defensively at all.

“It’s just been a constant focus daily. And it does help keeping those rebound attempts.”

Lopez has a daily drill regimen designed to improve his rebounds. But can he be a legit 20-10 guy?

“We’ll see. Hopefully,” Lopez said.

What was so irritating last season was everyone knew he could do it. Maybe not rewrite the record book, but do more.

“Brook should be a perennial All-Star. I’ve been saying definitely top five centers, especially offensively,” said Deron Williams, whose point guard presence makes Lopez so much more effective. “Where he can improve is defensively and rebounding, and he’s working to take those steps … I’m going to stay on him and the coaching staff is going to stay on him to make sure he achieves those goals.”

Lopez seemingly has remained unaffected through all of the Dwight Howard Nets trade talk. He says he doesn’t pay attention. He likes it here, wants to stay.

“I’ve got a lot of confidence in him,” Johnson said. “But it’s about consistency and that’s what we’re looking for, night in and night out.